By Fergal Keane
BBC News, Sarawak
Campaigners on the island of Borneo are trying to stop loggers doing further damage to the homeland of the Penan tribe, whose independent and self-sufficient community is as vulnerable as their jungle home.
Suddenly I lost my footing. My right foot slid into a deep hole, the mud sucking it down, until I was trapped.
Around 10,000 Penan live in Sarawak, Malaysia
It felt as if the ooze were alive, wrapping itself around my leg, determined to hold me there.
I reached out to grab a branch so that I could gain balance. But I recoiled instantly. The branch was stippled with thorns.
A colleague - who had made the same mistake - screamed behind me.
After a few anxious minutes scanning the foliage, I saw a thick and smooth vine which I caught hold of, pulling myself out of the morass, but leaving my shoe behind.
Ahead of me on the trail our guide Petrus was chuckling. I doubt he had ever seen before a Westerner so plump and preposterously unfit, attempting to navigate the jungle.
As he moved ahead, Petrus would emit an occasional high pitched yell. This, he explained, was a call used between the Penan hunters to communicate in the dense forest.
I was convinced I heard murmurs nearby. It was hunters passing like spirits through the shimmering green of the forest.
After about 15 minutes we heard a pounding noise. Petrus stopped and called out. And he was answered immediately. We had found Padang and his family.
Coming into the clearing I saw the patriarch raise a large club and bring it pounding down onto a mush of sago palm.
The pulp from the sago palm provides the Penan with a staple of their diet, a sticky brown goo that is usually served with the meat of wild boar, barking deer, squirrel or even python.
The Penan survive by hunting and eating pulp from the sago palm
Padang did not know what age he was. But I guessed he was in his 50s or 60s.
His hair was still jet black and hung to his shoulders. It was cut high off the forehead, in a rough fringe that gave full expression to the warmth and mischievousness of his face.
Padang still wore a loincloth, something only the older members of the tribe do now, but the effect was somewhat slightly offset by the presence on his wrist of a digital watch, whose numbers flickered in the forest gloom.
As well as Padang, there was his grandson-in-law, granddaughter, grandson and great-grandson, all working in the small clearing.
They had set up temporary camp beside a stream where the young women could wash and press the sago harvested by the men. The little boy was given the task of minding the baby.
The group did not seem to speak much to one another. That, and the ease with which they moved, all contributed to a feeling of serenity.
The pounding of the sago did not interfere with the other noises of the forest, of bees and cicadas and birds high in the canopy. It did not disturb, perhaps because it has been heard for as long as humans have hunted and gathered here. The Penan are simply part of this landscape.
It is all too easy to romanticise indigenous peoples, to invest them with nobility or conjure images of paradise before the fall. The Penan are not angelic or mystical.
Could logging activities and traditional ways of life co-exist?
What makes them engaging is their humanity, a gentleness which is not common in our age.
Padang told me that he regarded the jungle as his mother and father. And he said this without artifice, without the calculation of the professional spokesman.
And he spoke like one who is bereft, for the forest is shrinking.
The loggers who serve the world's insatiable appetite for timber are cutting swathes through Sarawak's rainforest.
The Penan have tried to stop them with blockades and now lawsuits conducted on their behalf by human rights groups. But in the face of powerful loggers and their political backers, the Penan seem to be on the wrong side of what is called "development".
They are not a belligerent people. A local told me the Penan were the only tribe in the region who did not engage in head hunting in the old days. They disdained physical violence.
I followed them on the journey back to their camp on the outskirts of the village of Bario, in the Kelabit Highlands of Sarawak.
At the camp several children appeared along with Padang's brother, who had been getting the fire ready for supper. The men and women share the daily tasks pretty much equally.
Then everybody climbed onto a rough wooden platform and sat together as the evening food was handed around. It was the ubiquitous sago and some lumps of fire blackened barking deer.
I asked Padang if be believed this way of life would survive.
He did not answer the question directly. "We cannot change our life," he said. "This is our life."
But for all that, I think he knew enough of this age to understand that the world he knew was in its last days.
From Our Own Correspondent was broadcast on Saturday 14 July 2007 at 1130 BST on BBC Radio 4. Please check the programme schedules for World Service transmission times.